scholarly journals Application of Finite Element Power Flow and Visualization in Rolling Mill Vibration

2020 ◽  
Vol 162 ◽  
pp. 03003
Author(s):  
Biao Xiao ◽  
Xiaoqiang Yan
Keyword(s):  
Power Flow ◽  
Displacement Vector ◽  
Response Spectrum ◽  
Vibration Displacement ◽  
Harmonic Response ◽  
Flow Vector ◽  
Displacement Vectors ◽  
Color Vector ◽  
Vector Distribution ◽  
Flow Vectors

The power flow harmonic responses of the upper roll system are obtained by combining the speed solution and stress solution, and compare with the traditional harmonic response, we find that the traditional vibration displacement, velocity and acceleration harmonic response spectrum can’t completely reflect the reality of the vibration energy. The power flow vectors of the mill can be obtained with a color vector program developed independently. Compared with the vibration displacement vectors, we found that the displacement vector distribution of the mill is quite different from that of the power flow vector with the frequency of 104Hz: the displacement vector amplitude gradually increases from the bottom to the top of the mill, and the displacement vector is transmitted from bottom to top vertically. The power flow vector amplitude of the working roll and the intermediate roll is larger than that of the other parts, and power flow vectors present complex transfer directions. Similarly, when the considering frequency is taken as other values, the distribution of vibration displacement vector and power flow vector are also variable.

Spacetime Geometry

2018 ◽  
Author(s):  
David M. Wittman
Keyword(s):  
Coordinate System ◽  
Special Relativity ◽  
Displacement Vector ◽  
Proper Time ◽  
Plane Geometry ◽  
Spatial Displacement ◽  
Spacetime Geometry ◽  
Space And Time ◽  
Displacement Vectors

This chapter shows that the counterintuitive aspects of special relativity are due to the geometry of spacetime. We begin by showing, in the familiar context of plane geometry, how a metric equation separates frame‐dependent quantities from invariant ones. The components of a displacement vector depend on the coordinate system you choose, but its magnitude (the distance between two points, which is more physically meaningful) is invariant. Similarly, space and time components of a spacetime displacement are frame‐dependent, but the magnitude (proper time) is invariant and more physically meaningful. In plane geometry displacements in both x and y contribute positively to the distance, but in spacetime geometry the spatial displacement contributes negatively to the proper time. This is the source of counterintuitive aspects of special relativity. We develop spacetime intuition by practicing with a graphic stretching‐triangle representation of spacetime displacement vectors.

Research on the power sharing capacity of a dual power open-end winding PMSM drive system for vehicular applications

2021 ◽  
pp. 095440702110078
Author(s):  
Yifan Jia ◽  
Zhonghua Huang ◽  
Liang Chu ◽  
Xiaoxiang Na ◽  
Nan Xu ◽  
...  
Keyword(s):  
Power Flow ◽  
Permanent Magnet Synchronous Motor ◽  
Drive System ◽  
Power Sharing ◽  
Power Sources ◽  
Voltage Vector ◽  
Vector Distribution ◽  
Maximum Torque Per Ampere ◽  
Open End Winding ◽  
Dual Power

An open-end winding permanent magnet synchronous motor (OW-PMSM) fed by dual inverter is a competitive option for the drive system of dual power electric vehicles. It allows manageable power flow between two isolated power sources through the motor without requiring a DC/DC converter. Based on the mathematical model of the OW-PMSM and the principles of power sharing, this paper first compares the power sharing capacity among some existing torque regulation algorithms, including unit power factor (UPF) control, maximum torque per ampere (MTPA) control, and constant back electromotive force (CBE) control. Then a control algorithm named minimum voltage vector amplitude (MVVA) is presented, which features covering the maximum motor operating range and the maximum power sharing range under the linear voltage vector distribution. Simulation results confirm the validity of the proposed MVVA control, and demonstrate its advantages in vehicular applications.

Numerical Simulation of Gas Injection for CBM Openhole Cavity Completion Considering the Coal Vertical Fracture System

2011 ◽  
Vol 101-102 ◽  
pp. 298-301
Author(s):  
Xiao Yi Li ◽  
Zhi Ming Wang ◽  
Xin Wan ◽  
Yang Cao
Keyword(s):  
Coalbed Methane ◽  
Displacement Vector ◽  
Fluid Velocity ◽  
Stress Gradient ◽  
Fracture System ◽  
Vertical Fracture ◽  
Matrix Deformation ◽  
Vector Distribution ◽  
Tensile Fractures ◽  
Coal Reservoir

A discrete element numerical model simulating the process of gas pressurization in coalbed methane wells is built based on UDEC software. The model considers the unique vertical fracture system of the coal. Simulates the distribution of effective stress, pore pressure and the node displacement vector around the wellbore in the process of pressurization under different terrestrial stress conditions. The analysis shows that, reservoir fluid flow and matrix deformation in the pressurization of cavity completion can be better represented by taking coal's unique fracture system into consideration. Coal reservoir with anisotropic stress is more prone to rupture and collapse than that under isotropic condition. In the vertical fracture system, the discrepancy of the fluid velocity will lead to differences in formation stress gradient and help generate shearing fracture. Tensile fractures’ formation and growing trend can be reflected by nodal displacement vector distribution.

DETECTION OF MOVING OBJECT USING REMAINED BACKGROUND UNDER MOVING CAMERA

2007 ◽  
Vol 04 (03) ◽  
pp. 227-236 ◽  
Author(s):  
TAEHO KIM ◽  
KANG-HYUN JO
Keyword(s):  
Correlation Coefficient ◽  
Moving Objects ◽  
Displacement Vector ◽  
Image Sequence ◽  
Moving Object ◽  
Pixel Intensity ◽  
Current Image ◽  
Moving Camera ◽  
Lower Weight ◽  
Displacement Vectors

A background is a part that does not vary too much or change frequently in an image sequence. Using this assumption, an algorithm of reconstructing remained background and detecting moving objects for static and also moving camera is presented. For generating background, we detect regions that have high correlation coefficient compared within prior pyramid images from the current image. These detected regions are used for two process. First, we calculate the temporal displacement vector of each detected regions and classify clusters of pixel intensity based on camera movement. Second, we calculate temporally principal displacement vector using histogram of displacement vectors. Temporally principal displacement vector indicates camera movement. Finally we eliminate clusters which have lower weight than threshold, and combine remained clusters for each pixel to generate multiple background clusters. Experimental results show that remained background model and detected moving object under camera moving.

Determination of displacement vector on 180° domain boundary and polarization arrangements in lead titanate crystals

1997 ◽  
Vol 12 (2) ◽  
pp. 457-466 ◽  
Author(s):  
Chen-Chia Chou ◽  
C. Marvin Wayman
Keyword(s):  
Lead Titanate ◽  
Displacement Vector ◽  
Domain Boundary ◽  
Polarization Vector ◽  
Dynamical Theory ◽  
Fringe Contrast ◽  
Displacement Vectors ◽  
Domain Boundaries ◽  
Contrast Analysis ◽  
Diffraction Patterns

180° domain boundaries in flux-grown lead titanate single crystals show intriguing domain boundary extreme fringe contrast using transmission electron microscopy. Symmetrically distributed domain boundaries with alternate contrast have been observed, indicating that opposite displacement vectors exist one by one at boundaries. If appropriate reflection vectors were employed, an inclined domain boundary shows reversed fringe contrast. An analysis based upon the two-beam dynamical theory and a rule similar to stacking-fault contrast analysis was employed to predict the geometric configuration of a 180° domain boundary using the extreme fringe contrast (EFC) behavior. Appropriately choosing reflection vectors and utilizing the EFC reversal, a displacement vector as well as the polarization vector arrangement across a 180° domain boundary can be unambiguously identified. Employing the information derived from diffraction patterns and a tilting experiment across a nearby 90° boundary, the whole polarization configuration can be uniquely determined.

Stacking faults in magnetite from the Allende meteorite

1992 ◽  
Vol 200 (3-4) ◽  
Author(s):  
Wolfgang Friedrich Müller ◽  
Gerhild Müller-Beneke
Keyword(s):  
Fault Plane ◽  
Displacement Vector ◽  
Stacking Faults ◽  
Stacking Fault ◽  
Cation Sublattice ◽  
Triple Junctions ◽  
Lattice Vector ◽  
Displacement Vectors

AbstractStacking faults of the type 1/4 〈110〉 {110} have been observed in magnetic crystals of a chondrule from the meteorite Allende. A stacking fault assemblage of all six possible orientations of the faults has been analysed in detail. The displacement vector 1/4 〈110〉 is always perpendicular to the corresponding fault plane {110}. It is shown that other orientations of fault planes would lead to unallowed short distances between closely neighboured cations. Three fault planes may meet in triple-junctions, their three displacement vectors adding up to a lattice vector. The stacking faults affect only the cation sublattice and form probably during growth of the magnetite crystals.

scholarly journals Determining Land Management Zones Using Pedo-Geomorphological Factors in Potential Degraded Regions to Achieve Land Degradation Neutrality

Land ◽  
2019 ◽  
Vol 8 (6) ◽  
pp. 92 ◽  
Author(s):  
Ali Keshavarzi ◽  
Vinod Kumar ◽  
Eduardo Leonel Bottega ◽  
Jesús Rodrigo-Comino
Keyword(s):  
Land Management ◽  
Land Degradation ◽  
Agricultural Land ◽  
Clay Content ◽  
Sampling Point ◽  
Management Zones ◽  
Grid Sampling ◽  
Flow Vector ◽  
Management Plans ◽  
Flow Vectors

The proper delineation of site-specific management zones is very important in the agricultural land management of potentially degraded areas. There is a necessity for the development of prospective tools in management plans to correctly understand the land degradation processes. In order to accomplish this, we present a pedo-geomorphological approach using soil texture, land elevation and flow vector aspects to distinguish different management zones and to discretize soil micronutrients. To achieve this goal, we conducted the study in the Neyshabur plain, Northeast Iran. For data collection, grid sampling (500 × 500 m) was used with 70 specific points. Soil samples were collected in triplicates from various sites as composite samples (0–30 cm) to analyse clay, Zn, Mn, Cu and Fe. Using the altitude information (obtained with GPS at each sampling point), flow vectors were also modelled for all selected points. Based on the values of altitude, flow vectors and clay, management zones were delimited using geographic information systems. The best data organization was obtained from the combination of clay + elevation + flow vector attributes, generating two different management zones. In this circumstance, the lowest fuzzy performance index (FPI) and modified partition entropy (MPE) values were generated. It can be observed that the management zone 1 (MZ1) is located in the areas with a lower elevation and higher content of clay. On the other hand, the MZ2 was characterized by areas with a higher elevation and lower clay content. This study concluded that the design of management zones, using pedo-geomorphological information could reduce the time and cost of sampling necessary to assess potentially degraded areas of land.

Perfecting the methods of monitoring the buildings and structures deformation

2020 ◽  
Vol 958 (4) ◽  
pp. 9-18
Author(s):  
Yu.N. Kornilov ◽  
O.S. Tsareva
Keyword(s):  
Coordinate System ◽  
Displacement Vector ◽  
Field Work ◽  
Relevant Information ◽  
Application Point ◽  
Displacement Vectors

The authors present the peculiarities of evaluating the parameters (module, direction and coordinates of the application point) of the displacement vector of the object’s deformation mark, its stabilitydegree is to be evaluated, and on this basis technologies simplifying the processes of performing field work necessary to obtain relevant information are discussed. Various options to implementpolar spatial intersection during observations from fixed stations are considered. In particular, if there aren’t any connecting marks between the instrument’s standing points, it is proposed to use a remote target or measure directional angles (magnetic azimuths) of reference directions. Methods for obtaining the coordinates and displacement vectors of deformation marks in the same coordinate system are considered, depending on the implementation of the polar spatial intersection. An example of implementing the proposed observation methodology on the example of the Hydrocorpus-1 building located at 29 Polytechnicheskaya st., St. Petersburg, Russia is presented. The results obtained indicate the correctness of the proposed methodology.

Vibrational Power Flow Analysis of Stiffened Plate and Shell Structures

2011 ◽  
Vol 66-68 ◽  
pp. 1897-1901 ◽  
Author(s):  
Xiang Zhu ◽  
Gong Yu Xiao ◽  
Tian Yun Li ◽  
Xiao Fang Hu
Keyword(s):  
Cylindrical Shell ◽  
Power Flow ◽  
Flow Analysis ◽  
Flow Characteristics ◽  
Input Power ◽  
Shell Structures ◽  
Stiffened Plate ◽  
Simply Supported ◽  
Plate And Shell ◽  
Flow Vectors

In this paper, the vibration and power flow characteristics of stiffened plate and cylindrical shell structures are investigated by using finite element method. The power flow formulas of basic shell structural elements are given at first. Then a simply supported plate and stiffened plate’s input power flow characteristics and power flow vectors are investigated. The effects of stiffeners in plates are discussed. For a simply supported cylindrical shell, the influence of the structural damping, viscous damper and stiffeners on the cylindrical shell’s input power flow characteristics and propagated power flow characteristics are discussed in detail. The power flow vectors are visualized to reveal the distribution of energy in the shell structures. Some useful conclusions are drown and helpful for the vibration control of plate and shell structures.

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